Film gate



Aug. 28, 1934. w H. BAUCH 1,971,365

FILM GATE Filed Aug. 23. 1933 IZ 3O 3 Inqe nbor, WiLLiam H. Beulah,

- 4 Attorneys.

Patented Aug. 28, 1934 PATENT OFFICE FILM GATE William H. Bauch, Shelbyville, Ind., assignor to Pembroke W. Cornelius, Indianapolis, Ind., doing business under the name and style of Cornelius Engineering Company Application August 23, 1933, Serial No. 686,419

9 Claims. (CI. 88-17) This invention relates to a motion picture projector and particularly to a film gate to be employed in the projector. A primary object of the invention is to provide a film gate which may be easily and quickly opened and closed by means of a structure which may be incorporated in a very compact unit and which at the same time will effectively align the film without damage thereto. A further important object of the invention is to provide means whereby the pressure applied on the film in passing through the gate may be regulated to be that amount desirable, which amount in practice is that which will retain the film against further motion between the intermittent jerking of the film through the gate.

These and other objects and advantages will become apparent to those versed in the art by the following description of the invention as illustrated in one particular form by the accompany- 0 ing drawing, in which Fig. 1 is a fragmentary side elevation of a structure embodying my invention;

Fig. 2, a top plan view with the gate in a closed position; 2 Fig. 3. a top plan view with the gate in the open position, and

Fig. 4, a vertical section on the line 4-4 in Fig. 2.

Like characters of reference indicate like parts throughout the several views in the drawing.

Referring to the drawing, the lens tube through which the light is directed in the usual manner is designated by the numeral 10. Spaced rearwardly of this tube at a distance therefrom is the usual plate 11 in front of which the film is to be passed. This plate 11 has the customary vertically disposed ribs 12 and 13 at the respective edges thereof which space the film forwardly of the face of the plate. At one side of this plate 11, here shown as the left side, I provide two horizontally disposed posts 14 and 15, the post 14 being spaced somewhat above the post 15. A head 16 is formed to have a central cylindrical opening therethrough defined by a rearwardly extending annular flange 17 and to have vertically upwardly and downwardly extending portions l8.and 19 respectively having their rear faces in a common vertical plane. Extending from these upper and lower portions are mounting brackets 20 and 21 respectively which are horizontally bored through to permit the brackets to be slidably carried on the posts 14 and 15. A length of tubing 22 is provided to fit snugly over the forwardly extending flange 1''! and is there secured by means of the screw 23. The length of the tube 22 is such that a portion thereof extends to within the tube 10 even when the head 16 is carried to its rearmost position. Preferably the diameter of the tube 22 is sufliciently less than the internal diameter of the tube 10 so that a clearance between the two tubes is provided. The location of the posts 14 and 15 and of the brackets 20 and 21 mounted thereon are such that the opening through the head 16 is centered about the aperture 24 through the plate 11, this aperture 66 being the one which admits light to be directed against the film.

The upper bracket 20 has a pin 25 secured therein and extending vertically upward therefrom. A shifting lever 26 is pivotally mounted by one end on a bracket 27 and extends horizontally over the bracket 20 to have the pin 25 extend upwardly through a longitudinal slot in the lever 26 and on over to the right side of the head.

A spring 28 is carried about the post 14 between the frame of the projector and the rear side of the bracket 20 to normally push the bracket and consequently the head 16 forwardly away from the plate 11. Thus the head 16 and its connected members are normally carried and positioned forwardly of the plate 11 to leave a gap between it and the rear face of the head 16. It is through this gap that the film 29 is positioned.

Along each vertical edge in the rear face of the head 16 is placed a pressure bar 30 and 31 re- 86 spectively to be in direct alignment with the respective ribs 12 and 13. Each of these bars 30 and 31 has an upper and lower post 32 and 33 respectively which slidably passes through the upper and lower extending portions of the head 16 to be pressed normally rearwardly by the leaf springs 34 and 35 which are mounted on the forward sides of these extending portions of the head 16. These bars 30 and 31 also are mounted over recessed portions in the face of the head 16 so that as they may be pushed forwardly, the bars may be retracted to within these recesses. Normally the bars are positioned by the springs 34 and 35 to project .rearwardly beyond the face of the head 16.

On the upper end of the head 16, that is, on the upwardly extending portion thereof, is

- mounted a transverse shaft 36 to be horizontally rotatable. On the right hand end of this shaft is mounted a wheel 3'7 to be tree to revolve thereon and is maintained in a fixed axial position, that is, it may not shift along the shaft 36. Toward the other end of the shaft is mounted a corresponding wheel 38 which is likewise revoluble about the shaft but which is also shiftable axially therealong. The wheel 38 is urged to the right along the shaft 36 by means of a spring 39 wrapped about the shaft. These wheels 37 and the gate is ready to be closed. This closing is effected by shifting the lever 26 by its outer free end against the pressure of the spring 28 so as to bring the bars 30 and 31 into contact with the edges of the film 29 to press those edges against the ribs 12 and 13. In order to retain the head 16 in this rear position, I provide a yoke 49 rockably supported by the frame of the projector so that the member may be swung around to strad die the outer end of the lever 26 as indicated in Figs. 1 and 2. In order that the pressure bars 30 and 31 may grip the film 29 with the desired amount of pressure, I provide a thumb-screw 40 to screw-threadedly pass through the cross member of the yoke 49 to bear against the forward edge of the lever 26, Fig. 2. In order to maintain this adjustment, a lock nut 41 is provided on the screw 40 to abut the end of the yoke 49. The screw 40 then serves as a convenient handle, by means of which the yoke 49 may be rocked into and out of engagement with the lever 26 as the gate is closed and opened.

It is to be seen from the foregoing description that a film gate is provided which has an exceptionally wide opening to permit the threading of the film therethrough as well as its removal and that at the same time the gate may be closed to provide the required amount of pressure against the film so that it may be properly stopped at each picture on the film. Other advantages are obvious to those skilled in the art, such advantages including the very few parts required in the assembly and in the accessibility and ease of shifting the operatingmember as well as the positive securing of the gate in the closed position.

While I have herein shown and described the one particular form of the invention as now best known to me, it is obvious that structural variations may be had without departing from the spirit of the invention and I do not therefore desire to be limited to that precise form beyond the limitations as may be imposed by the following claims.

I claim: i

1. For a projector having a frame, a lens tube, a film gate comprising a head having an annular flange telescoping in the porting the head to permit horizontal travel thereof toward and away from the frame, spring means yieldingly urging the head away from the frame, a shifting lever pivotally carried by the frame and engaging said head, and a member supported by the frame adapted to engage said lever when it is rocked to carry the head toward theframe.

2. For a projector having a frame, a film gate comprising a head, means supporting the head to permit horizontal travel thereof toward and away from the frame, spring means yieldingly urging the head away from the frame, a shifting lever pivotally carried by the frame and engaging said head, and a member supported by the frame adapted to engage said lever when it is rocked to carry the head toward the frame, said supporting lens tube, means sup means comprising posts carried by the frame and brackets carried by the head and slidably engaging the posts.

3. For a projector having a frame, a film gate comprising a head, means supporting the head to permit horizontal travel thereof toward and away from the frame, spring means yieldingly urging the head away from the frame, a shifting lever pivotally carried by the frame and engaging said head, and a member supported by the frame adapted to engage said lever when it is rocked to carry the head toward the frame, said lever engaging member comprising a yoke pivotally mounted on the frame to slip over the end of the lever.

4. For a projector having a frame, a film gate comprising a head, means supporting the head to permit horizontal travel thereof toward and away from the frame, spring means yieldingly urging the head away from the frame, a shifting lever pivotally carried by the frame and engaging said head, and a member supported by the frame adapted to engage said lever when it is rocked to carry the head toward the frame, pressure bars mounted on the head yieldingly urged toward said frame, and adjustable means carried by said lever engaging member spacing said head from the frame.

5. For a projector having a frame and a lens tube, a film gate comprising a head, posts supported by the frame horizontally guiding the head, a tube carried by the head telescoping with said lens tube, a head shifting lever rockably supported by the frame and pivotally engaging said head, and a lever engaging member supported by the frame to retain the head in a closed position.

6. For a projector having a frame and a lens tube, a film gate comprising a head, posts supported by the frame horizontally guiding the head, a tube carried by the head telescoping with said lens tube, a head shifting lever rockably supported by the frame and pivotally engaging said head, and a lever engaging member supported by the frame to retain the head in a closed position, said engaging member carrying loo an adjustable contact variably spacing the head from the frame, and film pressure bars yieldingly extending from the head toward the frame, the adjustment of said contact varying the degree of pressure by said bars on a film intervening between the bars and the frame.

7. For a projector having a frame and a lens tube, a film gate comprising a head, posts supported by the frame horizontally guiding the head, a tube carried by the head telescoping with said lens tube, a head shifting lever rockably supported by the frame and pivotally engaging said head, and a lever engaging member supported by the frame to retain the head in a closed position, said engaging member carrying an adjustable contact variably spacing the head from the frame, and film pressure bars yieldingly extending from the head toward the frame, the adjustment of said contact varying the degree of pressure by said bars on a film intervening between the bars and the frame, and a spring on one of said posts urging said head away from the frame.

8. For a projector having a frame, a film gate comprising a head, means supporting the head to permit horizontal travel thereof toward and away from the frame, elastically yielding contact members carried by the head, spring means yieldingly urging the head away from the frame,

pressing the bars so their faces toward the frame will project beyond the corresponding face of the head, spring means yieldingly urging the head away from the frame, a shifting lever pivotally carried by the frame and engaging said head, and a member supported by the frame adapted to engage said lever when it is. rocked to carry the head toward the frame.

WILLIAM H. BAUCH. 

